When the weather gets warm and tick season starts, most people worry about Lyme disease. But some Great Lakes states are a hot spot for another dangerous tick-borne disease -- the Powassen Virus.

Powassan triggers symptoms like fever, headache, vomiting. There also can be seizures and brain swelling, and it’s potentially fatal.

There have been dozens of reported cases of the virus from 2007 to 2016 in states along the Great Lakes, the U.S. Centers for Disease Control and Prevention says.

So far, there have been 25 reported cases in Minnesota, 20 in Wisconsin, and 17 in New York since 2007, according to the Centers for Disease Control. Meanwhile, some states reported only one case.

But experts say not to worry.

Bryon Backenson, an epidemiologist with the N.Y. Health Department, says the number of Powassancases isn’t so large when you consider how many tick bites happen overall -- between 30,000 and 40,000 per year.

“In some ways, what you should be concerned about when you’re out and about is the tick, not necessarily the disease, so there are a lot of precautionary measures that people can take,” he said. “Those include things like using repellant, walking in the center of paths, as opposed to brushing along the edges.”

No one knows why there are more cases in the Great Lakes states. Cornell University’s Laura Goodman works on a project that screens ticks for diseases like Powassan.

She says climate change could be a factor, because warmer winters extend the life cycle of ticks. And, she says folks should be on the lookout for more ticks this year.

“Every indication is that we’re going to have lots of ticks this summer,” she said. “We’re already seeing them being submitted this year we’ve already had ticks removed off of people and animals this spring.”

Experts say the quicker you can detect and remove the tick, the less likely you are to get a tick-borne disease.